Psychiatry Flashcards
(139 cards)
State the mechanism of action of SSRIs
Selective inhibition of serotonin reuptake. Increases availability of serotonin and enhances mood regulation.
State indications of SSRIs
1st line for:
- Depression
- Generalised anxiety disorder (GAD)
- Panic disorder
- Obsessive - compulsive disorder (OCD)
- PTSD
State cautions for SSRIs
- Omitted for mania
- Sertraline best for IHD patients
- Avoid in patients taking warfarin
State common side effects of SSRIs
- GI upset
- Anxiety + agitation
- QT interval prolongation (especially with citalopram)
- Sexual dysfunction
- Hyponatraemia
- Gastric ulcer
State common SSRIs
- Citalopram
- Fluoxetine
- Sertraline
- Paroxetine
- Escitalopram
Describe important considerations for monitoring patients on SSRIs
- Increased risk of impulsivity and suicide in people aged 18-25. Require review 1w post treatment commencement. With >25 can do 2-4w post.
- Continuation of antidepressants for at least 6m post remission to mitigate relapse risk.
Aetiology of serotonin syndrome
- SSRIs
- SNRIs
- MAOIs
- Tricyclic antidepressants
- MDMA and cocaine
Sx of serotonin syndrome
- Anxiety
- Agitation
- Restlessness
- Hyperthermia
- Tachycardia
- Tremor
Ddx of serotonin syndrome
- Neuroleptic Malignant Syndrome
- Same presentation but slower onset and longer duration
- Anticholinergic toxicity
- same presentation but decreased bowel sounds and urinary retention
Management of serotonin syndrome
- Discontinuation of offending drug + supportive care
- Extreme case: Cyproheptadine
State the mechanism of action of SNRIs
Increase serotonin and norepinephrine (adrenaline)
State indications for use of SNRIs
- First line for depression if SSRI not indicated or unsuccessful
- Licensed for use in GAD and panic disorder
- Contraindicated with history of heart disease and hypertension
Side effects of SNRIs
- Nausea
- Insomnia
- Tachycardia
- Agitation
State common SNRIs
- Duloxetine
- Venlafaxine
Summarise Mirtazepine
- Mirtazepine is 2nd line for management of depression.
- Preferred in cases with concern of weight loss and sleep
- Side effects include:
- Sedation
- Weight gain
- GI dysfunction
State the mechanism of action (Tricyclic Antidepressants) TCAs
- Block reuptake of serotonin and noradrenaline
- Also used as antimuscarinic
State common TCAs
- Amitriptyline
- Clomipramine
- Imipramine
State cautions for use of TCAs
- Previous heart disease
- Exacerbate schizophrenia
- Exacerbate long QT syndrome
- Urinary retention (avoid men with enlarged prostate)
State side effects of TCAs
Anticholinergic activity:
- Urinary retention
- Drowsiness
- Blurred vision
- Constipation
- Dry mouth
State signs of TCA toxicity
- Drowsiness
- Confusion
- Arrhythmias
- Seizures
- QT interval prolongation
State mechanism of action for Monoamine Oxidase Inhibitors (MAO-IS)
- Monoamine oxidase metabolises serotonin and noradrenaline.
- Inhibition -> elevation of serotonin
- Similar structure to amphetamines so also affects uptake and release of dopamine, noradrenaline and serotonin.
State cautions for use of MAO-IS
- Cerebrovascular disease
- Manic phase of bipolar disorder
- Severe cardiovascular disease
State side effects of MAO-IS
Hypertensive reactions: tyramine-containing foods to be avoided (cheese, marmite, salami, etc)
State common MAO-IS
- Moclobemide